Simple Blood Test to Predict Alzheimer’s Clinical Progression in Earliest Stages

Alzheimer’s disease is difficult to diagnose in its early stages, often when symptoms are not yet evident, making it challenging to predict the rate of cognitive decline or progression to more advanced stages such as dementia. The most reliable biomarkers for detecting and monitoring Alzheimer’s require invasive procedures, such as lumbar puncture or expensive imaging techniques like positron emission tomography (PET). These limitations hinder the ability to diagnose the disease early and monitor its progression effectively. Now, a blood test could accurately identify Alzheimer’s disease and predict how fast it will progress, making early diagnosis and monitoring more accessible and affordable. The study, published in the journal Neurology, reinforces the role of blood tests in the future of diagnosing and monitoring dementias.

In the study, researchers at the Sant Pau Research Institute (IR Sant Pau, Barcelona, Spain) analyzed levels of p-tau217, a specific form of tau protein associated with neurodegeneration, in a cohort of 731 individuals with and without cognitive impairment. The study participants were followed for up to 10 years, allowing the researchers to gather long-term data on the marker's reliability in predicting the disease's trajectory. The researchers found that p-tau217 levels correlated not only with the presence of Alzheimer’s disease but also with the rate of cognitive decline.

The study demonstrated that p-tau217 offers a better prognostic ability than other biomarkers, such as p-tau181, and can be used as a tool to identify individuals at higher risk of developing Alzheimer’s in the short or medium term. A blood test for detecting p-tau217 could provide valuable insights into the stage of the disease and how fast it will progress. Such a non-invasive test has potential applications in both clinical and research settings. It could also help in selecting patients for clinical trials and facilitate the development of disease-modifying treatments. Moving forward, the researchers aim to further explore the utility of p-tau217 in clinical settings and its potential for monitoring disease progression in Alzheimer’s patients.

“In a memory clinic, having access to this information through a blood test opens up possibilities that were previously limited to highly specialized centers,” said Dr. Ignacio Illán, researcher in the Neurobiology of Dementia group and neurologist at Sant Pau Hospital, who led the study.